/*******************************************************************************
心血來潮上SGU敲了道計算幾何~SGU的數據一如既往的BT啊!題意就是給定一個凸包,然後再給定若干
個點,詢問是否有至少K個點在凸包內,因爲數據規模比較大,O(n)的判定算法必然超時,AC核武的博客上有
篇講O(log n)的判定算法的博客,就是極角排序+二分,相當犀利~
*******************************************************************************/
#include <iostream>
#include <functional>
#include <algorithm>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <fstream>
#include <iomanip>
#include <sstream>
#include <utility>
#include <bitset>
#include <cctype>
#include <cstdio>
#include <limits>
#include <memory>
#include <string>
#include <vector>
#include <cmath>
#include <ctime>
#include <queue>
#include <stack>
#include <list>
#include <map>
#include <set>
using namespace std;
#define LOWBIT(x) ( (x) & ( (x) ^ ( (x) - 1 ) ) )
#define CLR(x, k) memset((x), (k), sizeof(x))
#define CPY(t, s) memcpy((t), (s), sizeof(s))
#define SC(t, s) static_cast<t>(s)
#define LEN(s) static_cast<int>( strlen((s)) )
#define SZ(s) static_cast<int>( (s).size() )
typedef double LF;
typedef __int64 LL; //VC
typedef unsigned __int64 ULL;
typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;
typedef pair<double, double> PDD;
typedef vector<int> VI;
typedef vector<char> VC;
typedef vector<double> VF;
typedef vector<string> VS;
template <typename T>
T sqa(const T & x)
{
return x * x;
}
template <typename T>
T gcd(T a, T b)
{
if (!a || !b)
{
return max(a, b);
}
T t;
while (t = a % b)
{
a = b;
b = t;
}
return b;
};
const int INF_INT = 0x3f3f3f3f;
const LL INF_LL = 0x7fffffffffffffffLL; //15f
const double oo = 10e9;
const double eps = 10e-7;
const double PI = acos(-1.0);
#define ONLINE_JUDGE
const int MAXN = 100004;
int n, m, k;
struct Point
{
int x, y;
}pnt[MAXN];
struct Segment
{
int vx, vy;
Segment() {}
Segment(Point po, Point pt)
{
vx = pt.x - po.x;
vy = pt.y - po.y;
}
LL operator * (const Segment & rhs) const
{
return LL(vx) * LL(rhs.vx) + LL(vy) * LL(rhs.vy);
}
LL operator ^ (const Segment & rhs) const
{
return LL(vx) * LL(rhs.vy) - LL(vy) * LL(rhs.vx);
}
};
bool cmpXY(const Point & lhs, const Point & rhs)
{
return lhs.y != rhs.y ? lhs.y < rhs.y : lhs.x < rhs.x;
}
bool cmpPK(const Point & lhs, const Point & rhs)
{
return (Segment(pnt[0], lhs) ^ Segment(pnt[0], rhs)) > 0; //逆時針的極角排序,>改<就是順時針的了
}
bool inPolygon(const Point & pt)
{
int low = 1, high = n - 2, mid = (low + high) / 2, res = -1;
bool sign = false;
int token;
LL flag[2];
while (low <= high)
{
mid = (low + high) / 2;
flag[0] = (Segment(pnt[0], pt) ^ Segment(pnt[0], pnt[mid]));
if (0 == flag[0])
{
sign = true;
token = mid;
break ;
}
flag[1] = (Segment(pnt[0], pt) ^ Segment(pnt[0], pnt[mid + 1]));
if (0 == flag[1])
{
sign = true;
token = mid + 1;
break ;
}
//if (flag[0] * flag[1] < 0) //NX的數據點,在這WA了兩次
if (flag[0] < 0 && flag[1] > 0 || flag[0] > 0 && flag[1] < 0)
{
res = mid;
break ;
}
if (flag[0] < 0 && flag[1] < 0)
{
low = mid + 1;
}
else
{
high = mid - 1;
}
}
if (sign)
{
if ((Segment(pnt[0], pt) * Segment(pnt[token], pt)) <= 0)
{
return true;
}
return false;
}
if (-1 == res)
{
return false;
}
return (Segment(pnt[mid], pt) ^ Segment(pnt[mid], pnt[mid + 1])) <= 0;
}
void ace()
{
Point pt;
int cnt;
while (scanf("%d %d %d", &n, &m, &k) != EOF)
{
for (int i = 0; i < n; ++i)
{
scanf("%d %d", &pnt[i].x, &pnt[i].y);
}
sort(pnt, pnt + n, cmpXY);
sort(pnt + 1, pnt + n, cmpPK);
pnt[n] = pnt[0];
cnt = 0;
while (m--)
{
scanf("%d %d", &pt.x, &pt.y);
if (inPolygon(pt))
{
++cnt;
}
}
puts(cnt >= k ? "YES" : "NO");
}
return ;
}
int main()
{
#ifndef ONLINE_JUDGE
freopen("in.txt", "r", stdin);
freopen("out.txt", "w", stdout);
#endif
ace();
return 0;
}
/*******************************************************************************
Test Data...
5 4 2
1 -1
1 2
0 4
-1 2
-1 -1
-2 -1
1 -1
0 1
2 3
*******************************************************************************/
SGU 253 計算幾何 判定點是否在凸包內
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